Take a boat tour in Bangkok and sail amongst the many floating markets and if you dare {maybe find some company to go with you) visit Bangkok by night.
Visit Chiang Mai in the mountains, an absolute must!
Visit the tribe with the women with the elefhant neck. They are fascinating people and still hold on to the tradition that a woman gets one copper ring per year around her neck.
If you do not have planned any hotels in front in Indonesia, you can go for a few day's relaxing on one of the thousand islands off the coast of Jakarta. Take one further away because the closest ones have poluted water due to the fisher villages who float around.
Mount Bromo on Java if still able to reach because its an active vulcano but the trip is magnificent. You start before dawn decending in the still bigger crater where Mount Bromo is in, you have a trip of about an hour on foot in this crater and then a climb to the edge of Bromo to watch the sun come up. Wonderfull experience.
If you have time, take the ferry from Java to Sulawesi. A one time experience to be on deck with thousands of people who make the trip also, making their dinner on little propane burners, chickens in their baskets. You can sail first class which is still cheaper then an airline ticket but do not expect first class as a Western, you will have the upper deck to yourself and a nice cabine to sleep in but thats it.
Visit Toraja land in the mountains, they are a tribe on themselves, have beautiful houses and a deep cultural history.
They burry their death until the family has enough money to do the ritual ceremony. Until then, the dead family member has still a place at their table and a bed to sleep in. Once enough money gathered they dig up the body and do the ritual ceremony of slaughtering a bull and then the family member is put in one of the many caves surrounding the area, simple coffin and a wooden face of the deceased is placed in front of the cave. After that its a feast to celebrate life.
Indonesia leads itself very good in transportation, just show up on the designated places where the little busses stop and you can either take one of them or share a jeep with some other travelers to the place you want to go, price is minimal and certainly if you can share with some other travelers.
Sri Lanka has some beatiful trips to offer and you can do it with a private driver but I am not sure how the coast line has recovered from the tsunami a couple of years back. The mountains are beautiful though with all the tea plantations as far you can see.
And now in return
I want you to bring back a bag of coffee beans for me from Toraja land if you plan to visit, these beans are the top of the top.
Have fun!
Acira